PaddleOCR/ppocr/data/imaug/make_pse_gt.py

86 lines
3.0 KiB
Python

# -*- coding:utf-8 -*-
from __future__ import absolute_import
from __future__ import division
from __future__ import print_function
from __future__ import unicode_literals
import cv2
import numpy as np
import pyclipper
from shapely.geometry import Polygon
__all__ = ['MakePseGt']
class MakePseGt(object):
r'''
Making binary mask from detection data with ICDAR format.
Typically following the process of class `MakeICDARData`.
'''
def __init__(self, kernel_num=7, size=640, min_shrink_ratio=0.4, **kwargs):
self.kernel_num = kernel_num
self.min_shrink_ratio = min_shrink_ratio
self.size = size
def __call__(self, data):
image = data['image']
text_polys = data['polys']
ignore_tags = data['ignore_tags']
h, w, _ = image.shape
short_edge = min(h, w)
if short_edge < self.size:
# keep short_size >= self.size
scale = self.size / short_edge
image = cv2.resize(image, dsize=None, fx=scale, fy=scale)
text_polys *= scale
gt_kernels = []
for i in range(1,self.kernel_num+1):
# s1->sn, from big to small
rate = 1.0 - (1.0 - self.min_shrink_ratio) / (self.kernel_num - 1) * i
text_kernel, ignore_tags = self.generate_kernel(image.shape[0:2], rate, text_polys, ignore_tags)
gt_kernels.append(text_kernel)
training_mask = np.ones(image.shape[0:2], dtype='uint8')
for i in range(text_polys.shape[0]):
if ignore_tags[i]:
cv2.fillPoly(training_mask, text_polys[i].astype(np.int32)[np.newaxis, :, :], 0)
gt_kernels = np.array(gt_kernels)
gt_kernels[gt_kernels > 0] = 1
data['image'] = image
data['polys'] = text_polys
data['gt_kernels'] = gt_kernels[0:]
data['gt_text'] = gt_kernels[0]
data['mask'] = training_mask.astype('float32')
return data
def generate_kernel(self, img_size, shrink_ratio, text_polys, ignore_tags=None):
h, w = img_size
text_kernel = np.zeros((h, w), dtype=np.float32)
for i, poly in enumerate(text_polys):
polygon = Polygon(poly)
distance = polygon.area * (1 - shrink_ratio * shrink_ratio) / (polygon.length + 1e-6)
subject = [tuple(l) for l in poly]
pco = pyclipper.PyclipperOffset()
pco.AddPath(subject, pyclipper.JT_ROUND,
pyclipper.ET_CLOSEDPOLYGON)
shrinked = np.array(pco.Execute(-distance))
if len(shrinked) == 0 or shrinked.size == 0:
if ignore_tags is not None:
ignore_tags[i] = True
continue
try:
shrinked = np.array(shrinked[0]).reshape(-1, 2)
except:
if ignore_tags is not None:
ignore_tags[i] = True
continue
cv2.fillPoly(text_kernel, [shrinked.astype(np.int32)], i + 1)
return text_kernel, ignore_tags